Drawbench



y 27, 1952 J. w. OFFUTT 2,598,190

DRAWBENCH Filed Jan. 23, 1946 2 SHEETS- SHEE'I l INVENTORI JOHN W 0FFU7 Hi5 ATTORNEY Patented May 27, 1952 John aunt. Ellw cs,

E es eno ts N w las r" Maste classes! t jii i 64 .43 3

" a s s (01. 205-4.).

This. invention relates to. draw-benches for re.- ducing. the. diameter or tubes, bars and the like. and more particularly. to. improved means for pushing tubes, bars and the likethrough forming mean such as reducing dies. f

'In the cold drawing t tubes: and bars, it has been conventional practice. to point or. reduce one. end of: such articles so. such end could beex: tended through the reducing die. and then-gripped byJjaw. members. mounted on a movable carriage which pulled. such. articles through. the reducing die. The. pointing of; the ends ofthe articlesv is.

costly-and in; addition the pointed. and must sub: seouently be. scrapped; It has heretofore. been. proposed'to. push such articles. through the dies. butthejmechanism.hasbeentoo cumbersomeand; so, lacking; in flexibility. of; adjustment to. accommodatelvarious. sizes as to, render the; same; come. men al-1's! un conomical;

t-isa rdin ly an. objector the. pr se t inventiontonrovide-a. dev ce tor s e w d -varie of elongated articles through a reducing die and simultaneously support them to prevent bending or buckling thereof.

It is another object to. provide a device for pushing elongated articles 'throug'h'a. reducing die and for simultaneously supporting the same" which is simplein design and rugged-and durable inoperation.

The ,foregoing, and. iurther. obj ects will: become apparent. from. the. following. description. when read m-conjunctionwiththe. accompanying draw n suherein:

Fi ure. 1 isa side elevation;

Eigure 2;, is. an. enlarged elevation, partly. in section of the forward end of Figure 1;

Figure 3 is a vertical section on line IIIIII of Figure 2; and

Figure 4 is a partial elevation of a modification.

Referring more particularly to the drawings, the numeral 2 designates an elongated article such as a thin-walled pipe, part of which has been reduced in diameter by being pushed through a die 4 by endless chains 5 revolving around sprockets 8 and idlers Ill.

The chains 6 are composed of inner connecting links l2 and outer links H mounted on pins I6. Disposed between the inner links l2 and outer links l4 are rollers l8 likewise carried on the pins IS. The outer links 14 are somewhat triangular in shape and have special gripping blocks mounted therebetween. The gripping blocks 20 have a plurality of aligned V-shaped grooves 22 or varying sizes to permit gripping various sizes oftubing.

EQ Z Qd ub n he weent e. canton ine; or the The tens on or. inner. legs of; the. chains; backed up. bytl .c 52 2.6; which supportthechains; by. reason Q1}'cbntacil;OfiiIZOllBKS; lfiwith 'rollerwaysi z-e. The'tracksn are. support d at; inte miss on ddles. 31!], which. are. connected by; cqlumns; one end of; which. is. adiustable bvxsl-e re to regulate the distance between theatres and. th reby. r ulat the... space. betwe. chains, The lower. track '26- is monnte. hannel sup ort. 3.5: with. a. flexiblelnressure .hose. 38. betwee the-supportive and thetrack. Q6; Th pressure exerted by. the. grip131.11g-bloek cone tr lled by th hos an in; which. the. desired; liq -t uid or air pressure is maintained.

The force necessary to push the tube nth-rou h the. d e 4.. sy upplied by the. frictional. effect. on the ube in he. veshaped; grooves 01% the. rinnin the 20; The. extent or this. force windenend n t amount. o th fluid nressurelinlthehosel and. the length. of: chain in. cont ct with. the tube.

opera on, Que. ubewflr follilllk anothermth; theyends. p eierably: abuttin so that. the lengt of? chainrtubecontactwill; e end; on he distance etwee thesnrqc setsfl ani lidl rs. t0:- Whentha whaleripped e we nthe .shaped; roonesto r t e. locks su por ed: very dire tion in. aplanesp rpend cu-le fio. tsaxisand cannotbends or.=buc k e-u de the. .x al compressive.tome-Jere. ingsit h ou hheme. l a gn thtfl 0- sun.

il-settles en h. 4.0; p en ushto a..- it; lfgdesirsdl, ush; prevent buckling by giving additional support can be installed in this space.

The die 4 is supported in a holder 42 which may be adjustable to bring the die in line with the aligned row of V-grooves being used or may have three openings 44 therein for positioning the die in line with such row of blocks.

In Figure 4, I have shown a modified form of apparatus wherein certain of the triangularshaped outer links I4 are replaced at certain intervals with straight links 46, so that the opposed gripping blocks are omitted at such places. This permits a pusher block 48 to be inserted in such space whichblock is pushed forwardly by contact with the next succeeding opposed pair of gripping blocks. The pusher block 48 can be dropped in this space behind the tube at the rear end of the chains and will drop out of the slot when it passes the center line of the sprockets 8, due to the chain and V-blocks changing from formed if sufiicient gripping pressure is applied to achieve the pushing force.

3. When the last tube of a run is being reduced, it loses the frictional grip as its rear end approaches the die, so a follower tube witha diameter slightly less than the die openin must be used to clear the last tube from the die. Since the follower tube is smaller, it will not be gripped very strongly by the gripper blocks and the follower block can be used to push it along.

Such manner of die reducing elongated articles overcomes the present necessity of pointing and thereby eliminates 'suchexpense and the loss due to scrapping such ends. Moreover, this greatly increases production per machine and man hour. since the operation is continuous as contrasted to the intermittent operation of conventional draw-benches.

While I have shown and described one specific embodiment of my invention, it will be understood that this embodiment is merely for the purpose of illustration and description and that various other forms may be devised within the scope of my invention, asdefined in the appended claims.

I claim:

1. Apparatus for pushing an elongated article through forming means by frictional gripping means and by a pusher block carried thereby and simultaneously supporting the article throughout the length of the unformed portion comprising a pair of endless chains having parallel opposed leg portions, opposed gripping blocks carried by said chains, each of said blocks having a plurality of aligned V-shaped grooves, certain of said opposed blocks being spaced apart to permit the insertion of a pusher block adapted to be pushed forwardly by the opposed blocks directly therebehind, a pusher block between at least one of said opposed pairs of spaced apart blocks, said block extending across the space between said chains and being in-contact with both the upper and lower opposed gripping blocks directly therebehind longitudinally extending supporting means for the opposed leg portions of said chains and fluid pressure means behind at 4 least one of said supporting means for exerting a predetermined pressure on an elongated article disposed between said chains.

2. Apparatus for pushing an elongated article through forming means by frictional gripping means and by a pusher block carried thereby and simultaneously supporting the article throughout the length of the unformed portion comprising a pair of endless chains having parallel opposed leg portions, opposed gripping blocks carried by said chains, certain of said opposed blocks being spaced apart to permit the insertion of a pusher block adapted to be pushed forwardly by the opposed blocks directly therebehind, a pusher block between at least one of said opposed pairs of spaced apart blocks, said block extending across the space between said chains and being in contact with both the upper and lower opposed gripping blocks directly therebehind longitudinally extending supporting means for the opposed leg portions of said chains and fluid pressure means behind at least one ofsaid supporting means for exerting a predetermined pressure on an elongated article disposedbetweensaid chains. Y

3. Apparatus for pushing an elongated article through forming means by frictional gripping means and by apusher block inserted therein and simultaneously supporting the article throughout the length of the unformed portion comprising a pair of endless chains having parallel opposed leg portions, and opposed gripping blocks carried by said chains, certain of said blocks being spaced apart to permit the insertion of a pusher block adapted to be pushedforwardly by the opposed blocks directly therebehind, a pusher block between at least one of said opposed pairs of spaced 'apartblocks, said block extending across the space between'said chains and being in contact with both the upper and lower opposed gripping blocks directly therebehind.

JOHN W. OFFUTT.

REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS Number Date a Westin May 1, 1945 

